Manufacture of strawboard



ma E. rnnmueron, or sr.

, in the known manner.

' may not Patented Apr, 19, 1927.

'UNITEDESTATES PATENT OF DAVIDS, PENNSYLVANIA, AND ALEX BROOKING DAVIS,

01 CINCINNATI, OHIO.

MANIIFACTUBE OI STRAWBOARD.

No Drawing.

For a long'period of time strawboard has been manufactured by variations of a process which involves the disintegration of the straw by means of lime or soda, washing the resulting pulp and converting'into board The resulting product contains compounds which are evidently volatile, since when used in the manufacture of containers for food products, for instance, the so-called flats and fillers for egg cases, the contents of the containers take on what is commonly called the strawboard odor and taste, which is objectionable in many respects.

The principal object of our invention is to provide inodorous strawboard, and to provide strawboard which 'wh-en used in the manufacture of containers for food products does-not impart objectionable odor or taste to the contents of the container; also to provide strawboard which i's-sterile.

Another objectof our invention is to provide a process for producing such inodorous and sterile strawboard, and to provide a process which is adapted to commercial use.

Other objects of ourinventio'n will 'be in part obvious and in part pointed out'hereinafter.

\Ve havefound that if either raw straw or disintegrated straw (pulp) is distilled with steam, the major portion or all of the volatile odorous compounds contained in the straw fibres may thereby be removed.

Straw is heavily contaminated with molds and bacteria, especially of the spore-forming variety, and even distillation with steam destroy all of these organisms. Germination may produce bacteria which will react upon small amounts of carbohydrates and other-organic constituents of the straw to produce odorous compounds, and it is, therefore, evident that a further improvement, would be the 1 complete sterilization ofthe straw or straw pulp at the time the volatile constituents are removed. We have accomplished this by adding to the straw or straw pulp inv the stills a quantity for the work, and we do not'restrict our selves to sodium fluoride. However, that Application filed April 18, 1925. Serial No. 24,273.

product was chosen as probably being lowest in cost for the purpose and large amounts may be used since it is recoverable in the filtrate.

In distilling the straw or straw pulp with steam only suflicient steam need be passed through the material to remove the volatile compounds, and since they are volatile at ordinary temperatures as well-as at the'temperature of boiling water, it is evident that they are capable of being removed at temperatures below that of steam at atmospheric pressure, Therefore, the volatile compounds can be removed by the use "of steam in an apparatus to which a fairly high vacuum has been applied, with a resulting saving in the amount of steam required and a reduced cost per ton of material treated.

The volatile compounds of straw impregnate all portions ofthe fibre, and steam distillation removes only that volatilized from the outer surface of the fibre, but all is removed by continuing the distillation for a period, since the volatile odorous compounds are water soluble and apparently rapidly diffuse out of the fibre or fibre cells. This may be accelerated by first putting the straw fibres (raw straw or pulp) under steam pressure in acl osed vessel, then quickly releasing the pressure, thereby breaking down the fibre or fibre cell walls and exposing the volatile compounds contained to a more rapid volatilizing action.

After the removal of the major portion of the volatile odorous compounds by means of steam distillation. the small remaining amount of volatile impurities may be removed or destroyed by means of ozonized air or the application of ozone to the mass The disinfectant may be recove ration of the fimltrate.

St1'a\\'board.;;whicli has been deodorized is applicable for packing many food products 'and the deodorized board may beused for .the manufacture of numerous kinds of food cartons and packing cases. Furthermore, sterile board or a board which is practically sterile should have many advantages over a non-sterile board for use in packing As many changes could be made in the above process, and many apparently widely ditl'ei'ent embodiments of the invention could .1 made without departing from the scope thereof, it is intended that all matter contaiiied in'the above description be interpreted as illustrative and not in a limiting sense. lt is to be understood that the term straw libre as used in the above description and in the appended claims refers to straw fibre in raw straw and also t0'straw fibre indisintegrated straw and in straw pulp.

\Vhat we claim is 1. St-rawlooard comprising disintegrated new straw disinfected andsteain distilled, the strawboard being inodorous and sterile.

2. As a new product suitable for the manufacture of food cartons and parts thereof, inodorous and sterile strawboard pulp comprising new straw disintegrated, disinfected and steam distilled.

-3. a new productsuitable for the man- I ufacture of food cartons and parts thereof,

inodorous and sterile strawboard pulp comprising new straw disintegrated, disinfected and steam distilled, and containing traces of a disinfectant.

4. As a new product suitable for food cartons and parts thereof, inodorous and sterile strawlooard comprising new straw disintcgrated, disinfected. and steam distilled, and containing traces of a disinfectant.

5. Asa new product suitable for the manufacture of food cartons and parts thereof, inodorous and sterile strawboard pulp comprising new straw disintegrated, disinfected and steam distilled, and containing traces of sodium fluoride. 1

6. As a new product suitable for food cartons and parts thereof, inodorous and sterile strawboard comprising new straw disintegrated, disinfected and steam distilled, and containing traces of sodium fluoride.

7 The process of manufacturing material suitable for food cartons and parts thereof,

which includes subjecting disintegrated new straw to the action of live steam in the presence of a disinfectant to render the same inodorous and sterile.

8. The process of manufacturing materials suitable for food cartons and parts thereof, which includes rendering disintegrated new straw inodorous and sterile by distilling out by means of steam the volatile odorous principles in the presence of a disinfectant.

9. The process of manufacturing material suitable for food cartons and parts thereof. which includes removing from disintegrated new straw the volatile odorous principles by the application thereto of steam in the presence of a disinfectant and permitting a .portion of the disinfectant to remain to maintain sterility.

10. The process of manufacturing inatcrials suitable for food cartons and parts thereof, which includes rendering disintegrated new straw inodorous and sterile by distilling out by means of steam the volatile odorous principles in the presence of a dis-' 14. The process of deodorizing and sterilizing straw f bre, which includes distilling straw fibre with steam iii the presence of sodium fluoride.

15. The process of deodorizing straw fibre, I

which includes distilling out the volatile compounds with steam, and accelerating the ALEX BROOKING DAVIS. 

